Book chapter: Léon C, Beck F. Health behaviors among people aged 55–85. Analysis of the 2010 Health Barometer. Saint-Denis: Inpes; 2014. 189 p. According to the latest estimates, neuropsychiatric disorders have become the leading contributor to the total burden of disease measured within the European Union. They account for 30.1% of this burden among women and 23.4% among men. Among these disorders, depression is already the largest contributor to this burden, ahead of cardiovascular diseases. In this chapter, we will discuss the state of mental health among people aged 55 to 85 as measured in 2010 using three indicators: major depressive episodes (MDEs), psychological distress, and suicidal ideation. The occurrence of a CDE in the past twelve months, as measured by the CIDI-SF (Composite International Diagnostic Interview Short Form), corresponds to a pathological state of profound sadness and/or loss of interest in daily activities requiring medical and psychological care. Older adults with depressive symptoms face a number of negative consequences, including functional decline (cognitive and physical) that is highly debilitating for managing daily life, a reduced quality of life, comorbidities—including cardiovascular conditions—and higher mortality, particularly from suicide.[excerpt from chapter]